An enema infusion flow rate pressure control system

Abstract

The embodiment of the application provides a kind of enema infusion flow rate pressure control system, it is related to medical instrument technical field, including liquid storage module, delivery module, infusion pipeline, double pressure sensor, flow detection module, pressure buffer module, backflow detection module, control module and anal tube assembly;Control module calculates dynamic compliance index according to the differential pressure of double pressure sensor and flow data, and adjusts infusion flow rate accordingly;Control module drives delivery module to generate micro-amplitude flow pulse, extracts pressure wave attenuation rate and reflection time to assess intestinal state;Pressure buffer module absorbs transient pressure peak;Backflow detection module monitors reverse flow;System automatically switches lubrication dilation, treatment delivery and retention maintenance three stages according to dynamic compliance index and pressure wave feedback.The application realizes the dynamic adjustment of enema parameters according to the real-time state of intestinal tract, improves the treatment safety, comfort and drug retention effect.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an enema infusion flow rate and pressure control system. Background Technology

[0002] Most existing anorectal enema equipment uses gravity infusion or simple pump infusion to deliver medication. Its control parameters usually only include flow control or pressure limitation control. Due to significant differences in rectal and colon volume, intestinal wall elasticity, and intestinal compliance among different patients, the therapeutic effects produced under the same flow or pressure conditions vary greatly. Some patients are prone to problems such as intestinal spasm, abdominal distension and pain, reflexive drainage, or even intestinal wall damage during enema.

[0003] Some existing enema devices are equipped with pressure sensors for pressure monitoring, but they usually only monitor a single point of pressure or a single flow parameter. This cannot accurately reflect the actual expansion state of the intestine after the drug enters the intestine, nor can it dynamically adjust to real-time changes in intestinal compliance. When patients experience intestinal spasms or rejection reactions, the system often stops the infusion directly, affecting the continuity of treatment and the retention effect of the drug.

[0004] To address the aforementioned issues, there is an urgent need for an enema infusion flow and pressure control system that can automatically adjust the infusion flow and pressure based on the real-time state of the intestines. Summary of the Invention

[0005] To address the aforementioned issues, this application provides an enema infusion flow rate and pressure control system.

[0006] The enema infusion flow rate and pressure control system provided in this application adopts the following technical solution: An enema infusion flow rate and pressure control system includes a storage module, a delivery module, an infusion line, a first pressure sensor, a second pressure sensor, a flow detection module, a pressure buffer module, a backflow detection module, a control module, and an anal tube assembly. The delivery module is connected to the storage module. One end of the infusion line is connected to the delivery module, and the other end is connected to the anal tube assembly. The first pressure sensor is located on the infusion line at the outlet of the delivery module to detect the delivery pressure at the front end of the line. The second pressure sensor is located on the infusion line near the proximal end of the anal tube assembly to detect the actual infusion pressure before the medication enters the intestine. The flow detection module is located on the infusion line. The control module is connected to the first pressure sensor, the second pressure sensor, the flow detection module, and the delivery module. The control module is connected to the module signal. It calculates the pressure difference based on the detection values ​​of the first and second pressure sensors. The control module drives the delivery module to periodically generate micro-amplitude flow pulses and adjusts the infusion flow rate of the delivery module according to the changing trend of the dynamic compliance index. The pressure buffer module is located in the middle of the infusion line to absorb instantaneous pressure peaks during the infusion process. The backflow detection module is located on the backflow branch to detect reverse flow and send the detection result to the control module. When the reverse flow exceeds a set threshold, the control module controls the delivery module to enter the slow-release infusion mode, adjusts the current infusion flow rate to 40% to 60% of the initial flow rate, maintains it for a preset time, and then re-detects the pressure and backflow status. After the system stabilizes, the normal infusion flow rate is gradually restored.

[0007] Optionally, the control module performs bandpass filtering on the pressure signal acquired by the second pressure sensor, with a filtering frequency band of 0.5Hz to 5Hz, and extracts the pressure response curve after micro-pulse injection. The control module obtains the pressure wave attenuation rate and pressure wave reflection time based on the pressure response curve. The pressure wave attenuation rate is calculated by the ratio of the peak value of the reflected wave in the pressure response curve to the peak pressure at the start point of micro-pulse injection. The pressure wave reflection time is calculated by the time difference between the start time of micro-pulse injection and the time when the first reflected wave peak appears. When the pressure wave attenuation rate increases and the reflection time decreases, the control module reduces the infusion rate of the delivery module. When the pressure wave attenuation rate decreases and the reflection time increases, the control module increases the infusion efficiency of the delivery module.

[0008] Optionally, the period of the micro-flow pulse is 10 to 30 seconds, the duration of each micro-pulse is 0.5 to 2 seconds, and the amplitude of the micro-pulse is less than 10% of the normal infusion flow rate.

[0009] Optionally, the reflux detection module includes a one-way reflux channel and a micro flow detector. A one-way valve is provided in the one-way reflux channel, and the opening direction of the one-way valve is from the proximal end of the anal tube assembly to the liquid storage module. The micro flow detector is provided in the one-way reflux channel to detect reverse flow. The set threshold is 15% to 20% of the forward set flow. The duration of the sustained-release perfusion mode is 30 seconds to 120 seconds.

[0010] Optionally, the system automatically divides the intestinal state into a lubrication and expansion phase, a treatment delivery phase, and a retention and maintenance phase. In the lubrication and expansion phase, the control module controls the delivery module to operate at 20% to 40% of the target treatment flow rate. When the dynamic compliance index shows an upward trend in multiple consecutive pulse detections, it automatically switches to the treatment delivery phase. In the treatment delivery phase, the control module adjusts the infusion flow rate of the delivery module based on the dynamic compliance index and pressure wave feedback results. In the retention and maintenance phase, the control module reduces the infusion flow rate to 10% to 20% of the target treatment flow rate and maintains stable pressure. The switching between each phase is automatically completed based on the dynamic compliance index and pressure wave feedback results.

[0011] Optionally, the pressure buffer module includes an elastic buffer chamber, a flexible diaphragm, and a return spring. The elastic buffer chamber is connected to the infusion line to form a variable volume space. The flexible diaphragm divides the elastic buffer chamber into a liquid chamber and a gas chamber. The liquid chamber is connected to the infusion line. The return spring is disposed in the gas chamber and applies a preload force to the flexible diaphragm in the direction of the liquid chamber.

[0012] Optionally, the target treatment flow rate during the treatment delivery phase is 50 ml / min to 300 ml / min. When the dynamic compliance index drops below 60% of the initial value or the pressure wave attenuation rate increases by more than 30% of the initial value, the control module automatically reduces the infusion flow rate of the delivery module.

[0013] In summary, this application includes at least one of the following beneficial technical effects: This invention uses a first pressure sensor and a second pressure sensor to detect the outlet pressure of the delivery module and the proximal pressure of the anal tube assembly, respectively. Combined with real-time flow data obtained by the flow detection module, a dynamic compliance index based on micro-amplitude pulse excitation is constructed. This parameter directly reflects the ability of the intestine to accept the drug solution under unit pressure change, which improves the conventional pipeline fluid parameter monitoring to real-time assessment of the biomechanical characteristics of the intestine, realizing a technological leap from passive monitoring to active sensing.

[0014] This invention monitors reverse flow in real time using a backflow detection module. When an intestinal rejection reaction is detected, the infusion is not stopped directly. Instead, a slow-release perfusion mode is entered, and the flow rate is adjusted to 40% to 60% of the initial flow rate and maintained for 30 to 120 seconds. Under continuous low-flow perfusion conditions, the intestinal spasm is allowed to subside before the flow is gradually restored. This mechanism avoids continuous stimulation of the intestinal wall caused by forced perfusion and prevents treatment interruption and anal tube blockage caused by completely stopping the infusion, significantly improving the continuity and success rate of enema treatment.

[0015] This invention achieves multi-dimensional assessment of intestinal patency, effective volume, and intestinal wall tension by superimposing micro-amplitude flow pulses on normal infusion and extracting pressure wave attenuation rate and reflection time. The pressure wave feedback mechanism and dynamic compliance index complement each other, improving the reliability and control accuracy of intestinal status assessment.

[0016] This invention divides the enema process into three stages: lubrication and expansion, therapeutic delivery, and retention and maintenance. The switching between each stage is automatically completed based on the dynamic compliance index and pressure wave feedback results, realizing true personalized adaptive control and adjusting the perfusion strategy according to the real-time response of each patient's intestine.

[0017] This invention utilizes a mechanical buffer structure comprised of an elastic buffer chamber, a flexible diaphragm, and a return spring in the pressure buffer module. This structure physically absorbs and releases instantaneous pressure shocks before the electronic control system responds, creating a dual safety guarantee of active electronic control and passive mechanical protection, further reducing the risk of intestinal wall damage. Detailed Implementation

[0018] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise. It should also be understood that in the following embodiments of this application, “at least one” and “one or more” refer to one, two, or more than two. The term “and / or” is used to describe the relationship between related objects, indicating that three relationships may exist; for example, A and / or B can indicate: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character “ / ” generally indicates that the preceding and following related objects are in an “or” relationship.

[0019] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0020] The present invention will now be described in further detail.

[0021] This application discloses an enema infusion flow rate and pressure control system, including a liquid storage module, a delivery module, an infusion pipeline, a dual pressure detection module, a flow detection module, a pressure buffer module, a backflow detection module, a control module, and an anal tube assembly.

[0022] The reservoir module is used to store enema fluid or therapeutic solutions. It can be a reservoir bag or bottle with a capacity of 500ml-2000ml. The reservoir module has a filling port at the top and a dispensing port at the bottom, which is sealed to the infusion tubing. The delivery module is connected to the dispensing port of the reservoir module via the infusion tubing. The delivery module uses a peristaltic pump structure, comprising a pump body, pump tubing, and roller assembly. The roller assembly is driven by a motor to rotate, and the rollers sequentially squeeze the pump tubing to generate positive delivery pressure, continuously delivering the medication from the reservoir module to the infusion tubing. The peristaltic pump's delivery flow rate is precisely controlled by adjusting the motor speed via a control module, with a flow control accuracy of ±5% of the set value. One end of the infusion tubing connects to the outlet of the delivery module, and the other end connects to the anal tube assembly. The anal tube assembly includes an anal tube and an anti-prolapse structure at the front end of the anal tube. The front end of the anal tube has a circular guide and one or more side holes through which the medication enters the patient's intestine.

[0023] A first pressure sensor and a second pressure sensor are installed on the infusion line between the delivery module and the anal tube assembly. The first pressure sensor is located at the outlet of the delivery module, at a distance of 5cm-15cm from the outlet, and is used to detect the delivery pressure at the front end of the line. The second pressure sensor is located at the proximal end of the anal tube assembly, at a distance of 2cm-8cm from the connection between the anal tube assembly and the infusion line, and is used to detect the actual infusion pressure before the drug enters the intestine. Both the first and second pressure sensors are medical-grade miniature pressure sensors, and the two pressure sensors are electrically connected to the control module.

[0024] A flow detection module is installed on the infusion line. The flow detection module is located on the infusion line between the first pressure sensor and the pressure buffer module. The flow detection module adopts an ultrasonic time-of-flight flow sensor or a thermal mass flow sensor. The flow detection module is electrically connected to the control module to acquire infusion flow data in real time and send it to the control module.

[0025] The control module includes a microprocessor unit, an analog signal acquisition unit, a storage unit, a display unit, and a drive control unit. The analog signal acquisition unit includes a multi-channel analog-to-digital converter, used to receive analog signals from the first pressure sensor, the second pressure sensor, the flow detection module, and the backflow detection module and convert them into digital signals. The storage unit includes non-volatile memory and random access memory. The non-volatile memory is used to store control programs, calibration parameters, and operating data, while the random access memory is used to temporarily store real-time acquired data. The display unit uses an LCD screen or a touch screen to display information such as pressure values, flow rates, dynamic compliance index C_dyn, pressure wave attenuation rate β, pressure wave reflection time T, and the current working stage in real time. The drive control unit is electrically connected to the drive motor of the conveying module and sends speed control signals to the drive motor based on the calculation results of the microprocessor unit.

[0026] The control module simultaneously receives data collected by the first pressure sensor, the second pressure sensor, and the flow detection module, and calculates the pressure difference: ΔP = P1 - P2, where P1 represents the pressure value detected by the first pressure sensor, P2 represents the pressure value detected by the second pressure sensor, and the pressure difference ΔP reflects the pressure loss of the drug solution in the infusion line from the outlet of the delivery module to the inlet of the anal tube assembly. This pressure loss is mainly composed of the pipeline resistance, the anal tube opening resistance, and the intestinal inlet resistance.

[0027] The control module establishes dynamic compliance assessment parameters based on pressure difference and flow data. Since the intestine is a viscoelastic biological tissue cavity, its expansion characteristics during drug infusion cannot be characterized by a single static pressure or a single flow value. In this invention, on the basis of normal infusion by the delivery module, the peristaltic pump of the delivery module is driven by the control module to periodically generate micro-amplitude flow pulses. The period of the micro-amplitude flow pulse is set to 10s-30s, the duration Δt of each micro-amplitude pulse is set to 0.5s-2s, and the amplitude of the micro-amplitude pulse is less than 10% of the normal infusion flow rate.

[0028] During each micro-pulse duration, the control module records the pressure change ΔP detected by the second pressure sensor during the pressure response rise and the real-time infusion flow rate Q detected by the flow detection module, and calculates the dynamic compliance index: C_dyn=Q×Δt / ΔP, where Q represents the real-time infusion flow rate during the micro-pulse, in milliliters per minute (mL / min), converted to milliliters per second for calculation, Δt represents the duration of the micro-pulse, in seconds, ΔP represents the pressure change detected by the second pressure sensor during the pulse duration, in kilopascals (kPa), and C_dyn is in milliliters per kPa per second. It characterizes the volume of drug entering the intestine per unit time under a unit pressure change, reflecting the intestine's dynamic acceptance capacity for drug infusion.

[0029] When the C_dyn value is high, it indicates that the intestine can accept a larger volume of drug solution under a unit pressure change, with a large volume expansion capacity and good compliance. The system allows for an increase in infusion flow rate to improve treatment efficiency. When the C_dyn value continues to decrease, it indicates that the intestinal expansion capacity is reduced or close to the volume saturation state. If high flow rate perfusion is maintained at this time, it may lead to excessive intestinal expansion, excessive intestinal wall tension, or even intestinal wall damage. Based on this, the control module reduces the delivery flow rate of the delivery module and slows down the pressure increase rate, so that the intestine can complete drug solution perfusion within a safe pressure range.

[0030] To further improve the accuracy of intestinal status assessment, the control module also uses micro-amplitude flow pulse excitation to obtain the pressure wave propagation characteristics of the intestine. The control module performs bandpass filtering on the pressure signal collected by the second pressure sensor, with the filtering frequency band set to 0.5Hz-5Hz to remove the fundamental frequency noise generated by the peristaltic pump operation and power frequency interference. The pressure response curve after micro-amplitude pulse injection is extracted. At the starting point of micro-amplitude pulse injection, the second pressure sensor detects a rapidly rising pressure peak. This peak corresponds to the positive pressure wave generated by the pulse injection. This pressure wave propagates distally along the intestinal wall and is reflected after encountering structures such as intestinal bends, narrowings, or the terminal ileocecal valve. The reflected wave returns along the intestinal wall to the position of the second pressure sensor, forming a second pressure peak.

[0031] The control module obtains the pressure wave attenuation rate β and the pressure wave reflection time T using the following method. The pressure wave attenuation rate β is calculated by the ratio of the peak value of the reflected wave in the pressure response curve to the peak value of the pressure at the starting point of the micro-amplitude pulse injection. The specific expression is: β=A_ref / A_inc, where A_inc represents the peak value of the positive pressure wave detected at the starting point of the micro-amplitude pulse injection, and A_ref represents the peak value of the reflected wave generated by the pulse excitation. The larger the value of β, the smaller the attenuation of the pressure wave during its propagation in the intestine, indicating better intestinal patency and sufficient expansion space. An increase in the value of β indicates increased intestinal resistance and reduced expansion space.

[0032] The pressure wave reflection time T is calculated by the time difference between the start of the micro-amplitude pulse injection and the appearance of the first reflection peak. A longer T value indicates that the pressure wave propagation path is longer or the propagation speed is slower, which usually corresponds to an increase in intestinal volume and better expansion capacity. A shorter T value indicates a decrease in the effective volume of the intestine or an increase in intestinal wall tension.

[0033] When the pressure wave attenuation rate β increases and the reflection time T decreases, it indicates that the intestinal expansion space is reduced and the intestinal wall tension is increased. The system automatically reduces the infusion rate to avoid excessive intestinal expansion. When the pressure wave attenuation rate β decreases and the reflection time T increases, it indicates that the intestinal expansion capacity is good and the volume is sufficient. The system allows for increased infusion efficiency to shorten the treatment time.

[0034] The pressure buffer module is located in the middle of the infusion line, between the flow detection module and the second pressure sensor. The pressure buffer module includes an elastic buffer chamber, a flexible diaphragm, and a return spring. The elastic buffer chamber is a closed cavity that communicates with the infusion line to form a variable volume space. The cavity wall is made of medical-grade rigid material, and the cavity volume is 5ml-20ml. The flexible diaphragm is located inside the elastic buffer chamber, dividing it into a liquid chamber and a gas chamber. The liquid chamber is connected to the infusion line, while the gas chamber is either open to the atmosphere through a vent or filled with compressed gas. The return spring is located inside the gas chamber, with one end fixed to the inner wall of the elastic buffer chamber and the other end connected to the flexible diaphragm, applying pressure to the flexible diaphragm. The pre-tightening force towards the liquid cavity ensures that when the pressure within the infusion tubing is within the normal range, the flexible diaphragm maintains its balanced position under the action of the return spring, and the liquid cavity volume is at its minimum. When the intestinal pressure suddenly increases and is transmitted in reverse along the infusion tubing, the increased pressure pushes the flexible diaphragm towards the gas cavity, allowing some medication to enter the liquid cavity. This increases the volume of the liquid cavity in the elastic buffer chamber, absorbing and releasing the instantaneous pressure peak in the infusion system. When the intestinal pressure returns to normal, the return spring pushes the flexible diaphragm back to its original position, pushing the medication in the liquid cavity back into the infusion tubing. Through this mechanism, the pressure buffer module effectively reduces the mechanical stimulation of the intestinal wall caused by pressure shocks resulting from intestinal spasms or changes in patient position.

[0035] The reflux detection module is located on the reflux branch, which connects the infusion tubing near the anal tube assembly to the reservoir module. The reflux detection module includes a one-way reflux channel and a miniature flow detector. A one-way valve is installed in the one-way reflux channel. The one-way valve opens from the proximal end of the anal tube assembly towards the reservoir module, meaning that medication is only allowed to flow back from the infusion tubing to the reservoir module, preventing medication from flowing from the reservoir module back to the infusion tubing. The miniature flow detector is located in the one-way reflux channel and is used to detect the flow rate of the reverse-flowing medication. The miniature flow detector is electrically connected to the analog signal input port of the control module via a signal cable and sends the detected reverse flow signal to the control module.

[0036] When a patient experiences a bowel reflex due to intestinal stimulation, the intestinal pressure increases, and some of the medication flows back along the anal tube assembly and infusion tubing. The backflow detection module detects this change in reverse flow and sends the result to the control module. When the reverse flow exceeds a set threshold, the control module determines that the patient has experienced an intestinal rejection reaction. The set threshold is 15%-20% of the forward set flow rate. For example, if the forward set flow rate is 100 ml / min, the reverse flow threshold is set to 15 ml / min to 20 ml / min.

[0037] Upon determining that the patient has experienced intestinal rejection, the system does not immediately stop the infusion but instead enters a sustained-release perfusion mode. The control module reduces the rotation speed of the delivery module by driving the control unit, adjusting the current infusion flow rate to 40%-60% of the initial flow rate. The duration of the sustained-release perfusion mode is set to 30-120 seconds. During the sustained-release perfusion, the control module continuously monitors the pressure data from the second pressure sensor and the reverse flow data from the reflux detection module. When the sustained-release perfusion duration reaches the set value, the control module re-detects the pressure and reflux status. If the pressure detected by the second pressure sensor returns to the normal range and the reverse flow detected by the reflux detection module drops below the threshold, the control module determines that the system has stabilized and gradually increases the rotation speed of the delivery module to restore the infusion flow rate to the normal level. The recovery rate is 10%-20% per minute of increase in the normal infusion flow rate. If the reverse flow exceeds the threshold again during the sustained-release perfusion or recovery process, the control module re-enters the sustained-release perfusion mode and starts timing again.

[0038] The entire enema process is automatically divided into three stages according to the intestinal state: lubrication and expansion, treatment delivery, and retention and maintenance. The switching between the three stages is automatically completed based on the dynamic compliance index C_dyn and the pressure wave feedback results, rather than relying on fixed time switching.

[0039] During the lubrication and expansion phase, the control module controls the delivery module to operate at a low infusion flow rate, set at 20%-40% of the target therapeutic flow rate. The purpose of this phase is to slowly inject a small amount of medication into the intestine at low flow and low pressure, allowing the intestine to gradually adapt to the presence of the medication and produce gentle expansion. At the same time, the lubricating effect of the medication reduces friction between the intestinal wall and the anal canal components. During this phase, the control module continuously monitors the changing trend of the dynamic compliance index C_dyn. When the C_dyn value shows an upward trend in three consecutive pulse detections and the increase exceeds 10% of the initial value, it indicates that the intestine has adapted to the perfusion and has good expansion capacity. The control module then automatically switches the system to the therapeutic delivery phase.

[0040] During the treatment delivery phase, the control module increases the rotation speed of the delivery module to raise the infusion flow rate to the target treatment flow rate, which is set from 50 ml / min to 300 ml / min according to clinical application needs. In this phase, the control module uses the dynamic compliance index C_dyn and pressure wave feedback parameters β and T as target parameters for dual closed-loop control. When C_dyn remains high and β remains stable or decreases, and T remains stable or increases, the system maintains the current infusion flow rate. When C_dyn shows a continuous downward trend or β increases and T shortens, the system automatically reduces the infusion flow rate. The treatment delivery phase continues until the predetermined drug delivery volume is completed or C_dyn decreases to below 60% of the initial value.

[0041] During the retention and maintenance phase, the control module reduces the rotation speed of the delivery module, lowering the infusion flow rate to 10%-20% of the target therapeutic flow rate. Simultaneously, it controls the delivery module to maintain a stable low-level output pressure, allowing the medication to remain in the intestine for a longer period to improve drug absorption and the therapeutic effect of retention enema. During the retention and maintenance phase, the control module continuously monitors pressure data. When the pressure detected by the second pressure sensor exceeds the safe pressure threshold or the backflow detection module detects reverse flow, the system automatically exits the retention and maintenance phase and enters the sustained-release perfusion mode or stops the infusion.

[0042] In one specific implementation, the infusion flow rate during the lubrication and expansion phase is set to 30 ml / min. C_dyn is continuously monitored until it rises to a stable value, after which the system automatically switches to the therapeutic delivery phase. The target therapeutic flow rate during the therapeutic delivery phase is set to 150 ml / min. The control module applies a micro-amplitude flow pulse every 20 seconds, with a pulse duration Δt of 1 second and a pulse amplitude of 8% of the normal infusion flow rate. The control module calculates C_dyn, β, and T values ​​within each pulse cycle and dynamically adjusts the rotation speed of the delivery module based on the comprehensive evaluation results of the three parameters. When C_dyn drops below 60% of the initial value or β increases by more than 30% of the initial value, the system automatically reduces the flow rate to 80 ml / min. After the drug delivery is completed, the system automatically switches to the retention and maintenance phase, reducing the infusion flow rate to 20 ml / min and maintaining stable pressure. Throughout the process, if the backflow detection module detects that the reverse flow exceeds 18% of the forward set flow rate, the system immediately enters the sustained-release perfusion mode, adjusts the flow rate to 50% of the initial flow rate, maintains it for 60 seconds, and then re-detects.

[0043] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. Any equivalent modifications or variations made by those skilled in the art based on the content disclosed in the present invention should be included within the scope of protection set forth in the claims.

Claims

1. A flow rate and pressure control system for enema infusion, characterized in that: The system includes a storage module, a delivery module, an infusion line, a first pressure sensor, a second pressure sensor, a flow detection module, a pressure buffer module, a reflux detection module, a control module, and an anal tube assembly. The delivery module is connected to the storage module. One end of the infusion line is connected to the delivery module, and the other end is connected to the anal tube assembly. The first pressure sensor is located on the infusion line at the outlet of the delivery module to detect the delivery pressure at the front end of the line. The second pressure sensor is located on the infusion line near the proximal end of the anal tube assembly to detect the actual infusion pressure before the medication enters the intestine. The flow detection module is located on the infusion line at the outlet of the delivery module. On the infusion line, the control module is connected to the first pressure sensor, the second pressure sensor, the flow detection module, and the delivery module. The control module calculates the pressure difference based on the detection values ​​of the first and second pressure sensors. The control module drives the delivery module to periodically generate micro-amplitude flow pulses and adjusts the infusion flow rate of the delivery module according to the changing trend of the dynamic compliance index. The pressure buffer module is located in the middle of the infusion line to absorb instantaneous pressure peaks during the infusion process. The backflow detection module is located on the backflow branch to detect reverse flow and send the detection result to the control module. When the reverse flow exceeds the set threshold, the control module controls the delivery module to enter the slow-release infusion mode, adjusts the current infusion flow to 40% to 60% of the initial flow, maintains it for a preset time, and then re-detects the pressure and reflux status. After the system stabilizes, the normal infusion flow is gradually restored.

2. The enema infusion flow rate and pressure control system according to claim 1, characterized in that: The control module performs bandpass filtering on the pressure signal collected by the second pressure sensor, with a filtering frequency band of 0.5Hz to 5Hz, and extracts the pressure response curve after micro-amplitude pulse injection. The control module obtains the pressure wave attenuation rate and pressure wave reflection time based on the pressure response curve. The pressure wave attenuation rate is calculated by the ratio of the peak value of the reflected wave in the pressure response curve to the peak pressure at the start point of the micro-pulse injection. The pressure wave reflection time is calculated by the time difference between the start time of the micro-pulse injection and the time when the first reflected wave peak appears. When the pressure wave attenuation rate increases and the reflection time decreases, the control module reduces the infusion rate of the delivery module. When the pressure wave attenuation rate decreases and the reflection time increases, the control module increases the infusion efficiency of the delivery module.

3. The enema infusion flow rate and pressure control system according to claim 2, characterized in that: The period of the micro-pulse is 10 to 30 seconds, the duration of each micro-pulse is 0.5 to 2 seconds, and the amplitude of the micro-pulse is less than 10% of the normal infusion flow rate.

4. The enema infusion flow rate and pressure control system according to claim 1, characterized in that: The reflux detection module includes a one-way reflux channel and a miniature flow detector. A one-way valve is installed in the one-way reflux channel, and the opening direction of the one-way valve is from the proximal end of the anal tube assembly to the liquid storage module. The miniature flow detector is installed in the one-way reflux channel to detect reverse flow. The set threshold is 15% to 20% of the forward set flow. The duration of the sustained-release perfusion mode is 30 to 120 seconds.

5. The enema infusion flow rate and pressure control system according to claim 1, characterized in that: The system automatically divides the infusion process into three stages based on intestinal condition: lubrication and expansion, therapeutic delivery, and retention and maintenance. During the lubrication and expansion stage, the control module operates the delivery module at 20% to 40% of the target therapeutic flow rate. When the dynamic compliance index shows an upward trend in multiple consecutive pulse detections, the system automatically switches to the therapeutic delivery stage. During the therapeutic delivery stage, the control module adjusts the infusion flow rate of the delivery module based on the dynamic compliance index and pressure wave feedback results. During the retention and maintenance stage, the control module reduces the infusion flow rate to 10% to 20% of the target therapeutic flow rate and maintains stable pressure. The switching between each stage is automatically completed based on the dynamic compliance index and pressure wave feedback results.

6. The enema infusion flow rate and pressure control system according to claim 1, characterized in that: The pressure buffer module includes an elastic buffer chamber, a flexible diaphragm, and a return spring. The elastic buffer chamber is connected to the infusion line to form a variable volume space. The flexible diaphragm divides the elastic buffer chamber into a liquid chamber and a gas chamber. The liquid chamber is connected to the infusion line. The return spring is located in the gas chamber and applies a preload force to the flexible diaphragm in the direction of the liquid chamber.

7. The enema infusion flow rate and pressure control system according to claim 5, characterized in that: The target treatment flow rate during the treatment delivery phase is 50 ml / min to 300 ml / min. When the dynamic compliance index drops below 60% of the initial value or the pressure wave attenuation rate increases by more than 30% of the initial value, the control module automatically reduces the infusion flow rate of the delivery module.